Malicious PDF — malware analysis report

Static analysis result for SHA-256 8438892c50e408b2…

MALICIOUS

PDF

83.8 KB Created: 2021-09-06 04:49:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 494aea391deb627022f35c605e6e14c9 SHA-1: af89a2badb6dd55c0070f177cb55da7e995167ec SHA-256: 8438892c50e408b293af0684dbf719ed2892297cd4375ef8d4e89f861b5a3f4f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to compromised websites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs suggest an effort to obscure the true destination and potentially track campaign effectiveness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=example+of+a+motivation+letter+pdf PDF link annotation
    • http://degrossier.nl/uploads/file/87661982602.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/494a8323279adf92cfdfffd745235a8f/woreroxorivet.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/3h2q5a721rn4prkv9313i2knad/delivitu.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610fbaba1ae0b---xinejunu.pdfIn PDF document text
    • http://euro-ex.com/pewofokoretunerirodabu.pdfIn PDF document text
    • http://fisioterapiasuzzara.it/userfiles/files/31390510278.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/db8fcb79e348147150d31caaaac9cde3/wawovedawesa.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/82018642609.pdfIn PDF document text
    • http://sushiosushi.com/uploads/files/fotonutazesig.pdfIn PDF document text
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/bigopetibanupadilidebop.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/9032e1582702694c0dca70cd4d07988b/397950929.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/00d914313a87c6e88b58f71b216562ac/witeroxa.pdfIn PDF document text
    • http://zl369.net/userfiles/file/51160134023.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/fapiwunekevomebonusavone.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a07d5364c78---ninopegojexeda.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/poman.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/98525223916.pdfIn PDF document text
    • http://labradory.pl/file/sojak.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/u2ti1q8dkahcqek6lbt4u6811b/37302245795.pdfIn PDF document text
    • http://pattarasawat.com/ckfinder/userfiles/files/vokokenepupivutifu.pdfIn PDF document text
    • http://feuerwehr-mittenwalde.de/mediathek/files/xavasiko.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/63217418694.pdfIn PDF document text
    • http://lenosada.sk/editor_uploads/files/82141503282.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16097dac637fb0---lunetogosaderatap.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/edlqh0bor9lut46m73892aemv2/88689565807.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1DF 10640 bytes
SHA-256: fe6332220c80c547d545dda2bd05c756eee340cedcf2bc947facb06db5ff3a00
font_01_sfnt_off0000fa26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA26 18016 bytes
SHA-256: 85a828e526759e79a5ee0095e9ef82059f7642367d132ffbf012f10b92e52ea8
font_02_sfnt_off0001291a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1